If you can find someone with a hydraulic "finger" brake, they can bend it for you. The finger brake has removable sections in order to make boxes and pans, etc. when working with flat sheet.
Edit: are you trying to bend box tubing or flat stock? The only clean way I know to bend box tubing is through the use of a mandrel bender. The bend radius is determined by the die used.
If you are building this out of flat stock, then a finger brake is the way to go. I have a 3-in-1 sheetmetal worker 52 inches long, and it will brake small sections of .125 wall plate. The brake section is a finger brake design
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
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